Automotive System Safety

10Summary and Conclusions

Background

The previous chapters have discussed automotive system safety. Automotive system safety includes functional safety, safety of the intended function (SOTIF), and safety from other hazards that are not functional. The definition of safety that is commonly used by automotive safety specialists who reference ISO 26262 includes “no unreasonable risk.” This definition is also referenced in ISO PAS 21448 for safety. It is appropriate to system safety since the unreasonable risk referenced is agnostic to the cause of this risk – the cause may be a functional failure or nonfunctional.

This definition links achieving safety to determining whether the residual risk is unreasonable: that is, whether the risk is greater than the risk that is acceptable based on societal norms. If a product puts the general public at a risk that is greater than those norms consider acceptable, then the product is not considered safe. It is assumed that the risk accepted by society today is consistent with societal norms; this includes risk that can be determined for a particular type of accident that is caused by a system's normal or malfunctioning behavior. It also includes the risk that a system presents to society if the methods used to develop that system – including elicitation of and compliance with system safety requirements – are not at least as comprehensive as those used for similar products in the field.

The risk imposed on the general public from exposure ...